my blackhawk s4 won't pump up any Weight it moves up nice and can lift small weight like a car battery but anything big it just stops , any ideas ? I used straight 30 weight oil on it and cleaned out some water and rusty oil.
30 weight oil on it, or in it? If it had water and rusty oil in the reservoir, you need to disassemble the hydraulics completely, clean it out and assess the seals.
